When you need some protection, say the St. Michael the Archangel prayer:
"St. Michael the Archangel, defend us in battle. Be our protection against the wickedness and snares of the devil. May God rebuke him, we humbly pray, and do thou o prince of the Heavenly Hosts, by the power of God, thrust into hell, Satan and all the other evil spirits, who prowl about the world seeking the ruin of souls. Amen"
Remember to keep the holy souls in your prayers, especially at Mass.